Cerebral perfusion imaging of live mice by fluorescent X-ray CT

Fluorescent X-ray CT (FXCT), which has high-contrast and high-spatial resolution, is being developed for in-vivo biomedical research. Since FXCT could depict the specific heavy atomic number elements in the order of picogram, the functional imaging resembling to single photon emission CT can be obtained. We have applied this technique for in-vivo and ex-vivo biomedical imaging. FXCT system consists of a silicon (111) double crystal monochromator, an x-ray slit system, a scanning table for object positioning, fluorescent x-ray detectors, and pin-diode detectors. Using non-radioactive iodine labeled IMP, cerebral perfusion of a live mouse was clearly demonstrated at a 1 mm spatial resolution and a 0.1 mm slice thickness. In addition, the structure of extracted mouse brain fixed by formalin was depicted much clearly at 0.5 mm spatial resolution due to the availability of long data acquisition time. Thus, the success of in-vivo FXCT imaging with high resolution allows starting to new approach of bio-imaging research.